1. Field of the Invention
The present invention relates to a refractive index matching tape adhering device used for optical connection.
2. Description of Related Art
As a connection method for optical fibers, methods are commonly used in which optical fibers, or ferrules into which optical fibers are inserted, are physically connected by joining. As a part for connecting, for example, a mechanical splice, an optical connector, or the like, can be used, and in general, in the case in which the part is used in a semi-permanent type connection, the mechanical splice can be effectively used, whereas in the case in which the part will be frequently connected and disconnected, the optical connector can be effectively used. In the both cases, a physical connection is carried out by pressing end faces of the optical fiber in an axial direction thereof, and in the case of the optical connector, the optical fiber is inserted in a ferrule so as to protect it since it is usually fragile, and a physical connection of the end faces of the optical fiber can thereby be carried out.
In this physical connection, connection characteristics are greatly influenced by positioning accuracy and the shape of the edge of the optical fiber. For example, in the case in which the angle of an edge is shifted or the shape of an edge is uneven, air is present between the edges of the joined optical fibers, and Fresnel reflection is increased at connection edges, and therefore, connection loss is increased. In particular, connection losses may be substantially increased in multicore optical connectors.
Various methods for overcoming this problem have heretofore been researched. For example, in Japanese Unexamined Patent Application Publication No. 2005-274839, a structure is proposed in which a transparent refractive index matching film having adhesive characteristics is directly mounted to an edge of an optical fiber.
An adhering process for a conventional refractive index matching film will be explained with reference to FIG. 5.
FIG. 5 is used to explain the case in which only optical fiber is used; however, the case in which optical fibers are connected using support materials, such as a ferrule, may also be similarly explained.
Reference numeral 1 indicates an optical fiber, and reference numeral 2 indicates a refractive index matching film.
As shown in FIGS. 5A and 5B, an optical fiber 1 is moved relative to a refractive index matching film 2 until an edge of the optical fiber 1 adheres to the refractive index matching film 2. Then, as shown in FIG. 5C, a part of the refractive index matching film 2 is separated in a state in which it is adhered to an edge of the optical fiber 1 using the adhesive characteristics of the refractive index matching film 2, by moving the optical fiber in a reverse direction, and the refractive index matching film 2 can be provided only at the edge of the optical fiber 1.
However, there are problems in that the refractive index matching film 2 having adhesive characteristics is easily contaminated by fine dust, oil from the hands, or the like, and in that handling is difficult in adhering.
In the present invention, a construction using a refractive index matching oil may be used for the same object; however, a construction in which the refractive index matching film is directly adhered is preferable, since the reliability of environmental resistance decreases over time, and in the case of the refractive index matching oil, is lower than that of the case of the refractive index matching film.